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Current Microbiology May 2024As a primary nutrient in agricultural soils, phosphorus plays a crucial but growth-limiting role for plants due to its complex interactions with various soil elements....
As a primary nutrient in agricultural soils, phosphorus plays a crucial but growth-limiting role for plants due to its complex interactions with various soil elements. This often results in excessive phosphorus fertilizer application, posing concerns for the environment. Agri-research has therefore shifted focus to increase fertilizer-use efficiency and minimize environmental impact by leveraging plant growth-promoting rhizobacteria. This study aimed to evaluate the in-field incremental effect of inorganic phosphate concentration (up to 50 kg/ha/P) on the ability of two rhizobacterial isolates, Lysinibacillus sphaericus (T19), Paenibacillus alvei (T29), from the previous Breedt et al. (Ann Appl Biol 171:229-236, 2017) study on maize in enhancing the yield of commercially grown Duzi® cultivar wheat. Results obtained from three seasons of field trials revealed a significant relationship between soil phosphate concentration and the isolates' effectiveness in improving wheat yield. Rhizospheric samples collected at flowering during the third season, specifically to assess phosphatase enzyme activity at the different soil phosphate levels, demonstrated a significant decrease in soil phosphatase activity when the phosphorus rate reached 75% for both isolates. Furthermore, in vitro assessments of inorganic phosphate solubilization by both isolates at five increments of tricalcium phosphate-amended Pikovskaya media found that only isolate T19 was capable of solubilizing tricalcium at concentrations exceeding 3 mg/ml. The current study demonstrates the substantial influence of inorganic phosphate on the performance of individual rhizobacterial isolates, highlighting that this is an essential consideration when optimizing these isolates to increase wheat yield in commercial cultivation.
Topics: Triticum; Phosphates; Soil Microbiology; Soil; Rhizosphere; Fertilizers; Paenibacillus; Phosphorus
PubMed: 38734822
DOI: 10.1007/s00284-024-03685-x -
ACS Chemical Biology Apr 2024Glycosyltransferases play a fundamental role in the biosynthesis of glycoproteins and glycotherapeutics. In this study, we investigated protein glycosyltransferase...
Glycosyltransferases play a fundamental role in the biosynthesis of glycoproteins and glycotherapeutics. In this study, we investigated protein glycosyltransferase FlgGT1, belonging to the GT2 family. The GT2 family includes cysteine S-glycosyltransferases involved in antimicrobial peptide biosyntheses, sharing conserved catalytic domains while exhibiting diverse C-terminal domains. Our studies revealed that FlgGT1 recognizes structural motifs rather than specific amino acid sequences when glycosylating the flagellin protein Hag. Notably, FlgGT1 is selective for serine or threonine -glycosylation over cysteine -glycosylation. Molecular dynamics simulations provided insights into the structural basis of FlgGT1's ability to accommodate various sugar nucleotides as donor substrates. Mutagenesis experiments on FlgGT1 demonstrated that truncating the relatively large C-terminal domain resulted in a loss of flagellin glycosylation activity. Our classification based on sequence similarity network analysis and AlphaFold2 structural predictions suggests that the acquisition of the C-terminal domain is a key evolutionary adaptation conferring distinct substrate specificities on glycosyltransferases within the GT2 family.
Topics: Amino Acid Sequence; Cysteine; Flagellin; Glycosylation; Glycosyltransferases; Paenibacillus
PubMed: 38562012
DOI: 10.1021/acschembio.4c00045 -
Biotechnology Letters Apr 2024Microbial pretreatment of lignocellulosic biomass holds significant promise for environmentally friendly biofuel production, offering an alternative to fossil fuels....
Microbial pretreatment of lignocellulosic biomass holds significant promise for environmentally friendly biofuel production, offering an alternative to fossil fuels. This study focused on the isolation and characterization of two novel delignifying bacteria, GIET1 and GIET2, to enhance cellulose accessibility by lignin degradation. Molecular characterization confirmed their genetic identities, providing valuable microbial resources for biofuel production. Our results revealed distinct preferences for temperature, pH, and incubation period for the two bacteria. Bacillus haynesii exhibited optimal performance under moderate conditions and shorter incubation period, making it suitable for rice straw and sugarcane bagasse pretreatment. In contrast, Paenibacillus alvei thrived at higher temperatures and slightly alkaline pH, requiring a longer incubation period ideal for corn stalk pretreatment. These strain-specific requirements highlight the importance of tailoring pretreatment conditions to specific feedstocks. Structural, chemical, and morphological analyses demonstrated that microbial pretreatment reduced the amorphous lignin, increasing cellulose crystallinity and accessibility. These findings underscore the potential of microbial pretreatment to enhance biofuel production by modifying the lignocellulosic biomass. Such environmentally friendly bioconversion processes offer sustainable and cleaner energy solutions. Further research to optimize these methods for scalability and broader application is necessary in the pursuit for more efficient and greener biofuel production.
Topics: Lignin; Cellulose; Biomass; Biofuels; Saccharum; Hydrolysis
PubMed: 38252364
DOI: 10.1007/s10529-023-03463-y -
Advanced Science (Weinheim,... Feb 2024Post-translational prenylations, found in eukaryotic primary metabolites and bacterial secondary metabolites, play crucial roles in biomolecular interactions. Employing...
Post-translational prenylations, found in eukaryotic primary metabolites and bacterial secondary metabolites, play crucial roles in biomolecular interactions. Employing genome mining methods combined with AlphaFold2-based predictions of protein interactions, PalQ , a prenyltransferase responsible for the tryptophan prenylation of RiPPs produced by Paenibacillus alvei, is identified. PalQ differs from cyanobactin prenyltransferases because of its evolutionary relationship to isoprene synthases, which enables PalQ to transfer extended prenyl chains to the indole C3 position. This prenylation introduces structural diversity to the tryptophan side chain and also leads to conformational dynamics in the peptide backbone, attributed to the cis/trans isomerization that arises from the formation of a pyrrolidine ring. Additionally, PalQ exhibited pronounced positional selectivity for the C-terminal tryptophan. Such enzymatic characteristics offer a toolkit for peptide therapeutic lipidation.
Topics: Dimethylallyltranstransferase; Tryptophan; Prenylation; Protein Processing, Post-Translational; Peptides
PubMed: 38059776
DOI: 10.1002/advs.202307372 -
Pakistan Journal of Biological Sciences... Jan 2023<b>Background and Objective:</b> Isolation and investigation of plant growth promoting bacteria on potato plants can provide significant information for the...
<b>Background and Objective:</b> Isolation and investigation of plant growth promoting bacteria on potato plants can provide significant information for the application of beneficial bacteria in potato production. This study aims to isolate and characterize endophytic bacteria isolated from potato roots. In addition, the potential application of endophytes in promoting potato growth under <i>in vitro</i> conditions was also investigated. <b>Materials and Methods:</b> The roots from 15 healthy potato plants were excised and surface sterilized by NaOCl and finally rinsed by sterilized water. The confirmed surface-sterilized roots were then aseptically cut into small fragments and spread onto the isolation media, followed by incubation at 27°C for up to 3 days. Six isolates that showed differences in colony morphology were selected for further investigation. All isolates were screened for IAA production, nitrogen fixation, and phosphate solubilization. <b>Results:</b> Five of the isolates were identified as <i>Bacillus</i> and isolate 30 was identified as <i>Paenibacillus alvei</i>. All isolates exhibited good IAA production. While Iso-27 had no nitrogen fixation activity, Iso-28 showed the highest level of nitrogen fixation activity (3.59 mg L<sup>1</sup>), four isolates (Iso-9, Iso-10, Iso-11, Iso-28) could solubilize phosphate, ranging from 49.64 g L<sup>1</sup> to 67.98 mg L<sup>1</sup>. After being inoculated with <i>in vitro</i> potato plants, isolates 9, 10, 28, 30, improved the stalk length, root number, fresh mass and dried mass of the potato plants. <b>Conclusion:</b> The four isolates can potentially be applied in <i>in vitro</i> potato culture.
Topics: Solanum tuberosum; Indoleacetic Acids; Plant Development; Bacillus; Phosphates
PubMed: 37902078
DOI: 10.3923/pjbs.2023.371.379 -
Environmental Science and Pollution... Oct 2023Management of crustacean shell waste (SW) through an eco-friendly technique is an environmental obligation to control pollution. The present study showed a novel...
Management of crustacean shell waste (SW) through an eco-friendly technique is an environmental obligation to control pollution. The present study showed a novel approach through the simultaneous application of proteolytic and chitinolytic bacteria to effectively degrade unprocessed crustacean SW. For this, the bacteria with concurrent chitinolytic and proteolytic activity (Bacillus subtilis, Priestia megaterium, or Bacillus amyloliquefaciens) were applied either alone or in combination with one proteolytic strain (Paenibacillus alvei) in the unprocessed lobster, crab, and shrimp SW. The method degraded the shells with high deproteinization (> 90%) and demineralization efficiency (> 90%). The degradation was confirmed through scanning electron microscopy. The highest weight loss achieved with shrimp, crab, and lobster shells was 93.67%, 82.60%, and 83.33%, respectively. B. amyloliquefaciens + P. alvei combination produced the highest weight loss in crab and lobster SW, whereas all combinations produced statistically similar weight loss in shrimp SW. There was a concurrent production of N-acetyl glucosamine (up to 532.89, 627.87, and 498.95 mg/g of shrimp, lobster, and crab shell, respectively, with P. megaterium + P. alvei and B. amyloliquefaciens + P. alvei in all SW) and amino acids (4553.8, 648.89, 957.27 μg/g of shrimp, lobster, and crab shells, respectively with B. subtilis + P. alvei in shrimp and B. amyloliquefaciens + P. alvei in crab and lobster). Therefore, it is concluded that, for the first time, efficient degradation of crustacean shell waste was observed using chitinolytic and proteolytic bacterial fermentation with the obtention of byproducts, providing a basis for further application in SW management.
PubMed: 37851246
DOI: 10.1007/s11356-023-30355-5 -
Microorganisms Aug 2023Honey bees coexist with fungi that colonize hive surfaces and pollen. Some of these fungi are opportunistic pathogens, but many are beneficial species that produce...
Honey bees coexist with fungi that colonize hive surfaces and pollen. Some of these fungi are opportunistic pathogens, but many are beneficial species that produce antimicrobial compounds for pollen conservation and the regulation of pathogen populations. In this study, we tested the in vitro antimicrobial activity of strains isolated from bee bread against (associated with European foulbrood disease) and three species that cause stonebrood disease. We found that methanol extracts of strains B18 and B195 inhibited the growth of at a concentration of 0.39 mg/mL. Bioactivity-guided dereplication revealed that the activity of the crude extracts correlated with the presence of diketopiperazines, a siderophore, and three unknown compounds. We propose that non-pathogenic fungi such as spp. and their metabolites in bee bread could be an important requirement to prevent disease. Agricultural practices involving the use of fungicides can disrupt the fungal community and thus negatively affect the health of bee colonies.
PubMed: 37630627
DOI: 10.3390/microorganisms11082067 -
Scientific Reports Aug 2023Pyruvylation is a biologically versatile but mechanistically unexplored saccharide modification. 4,6-Ketal pyruvylated N-acetylmannosamine within bacterial secondary...
Pyruvylation is a biologically versatile but mechanistically unexplored saccharide modification. 4,6-Ketal pyruvylated N-acetylmannosamine within bacterial secondary cell wall polymers serves as a cell wall anchoring epitope for proteins possessing a terminal S-layer homology domain trimer. The pyruvyltransferase CsaB from Paenibacillus alvei served as a model to investigate the structural basis of the pyruvyltransfer reaction by a combination of molecular modelling and site-directed mutagenesis together with an enzyme assay using phosphoenolpyruvate (PEP; donor) and synthetic β-D-ManNAc-(1 → 4)-α-D-GlcNAc-diphosphoryl-11-phenoxyundecyl (acceptor). CsaB protein structure modelling was done using Phyre2 and I-Tasser based on the partial crystal structure of the Schizosaccharomyces pombe pyruvyltransferase Pvg1p and by AlphaFold. The models informed the construction of twelve CsaB mutants targeted at plausible PEP and acceptor binding sites and K and k values were determined to evaluate the mutants, indicating the importance of a loop region for catalysis. R148, H308 and K328 were found to be critical to PEP binding and insight into acceptor binding was obtained from an analysis of Y14 and F16 mutants, confirming the modelled binding sites and interactions predicted using Molecular Operating Environment. These data lay the basis for future mechanistic studies of saccharide pyruvylation as a novel target for interference with bacterial cell wall assembly.
Topics: Paenibacillus; Bacillus; Mutagenesis, Site-Directed; Binding Sites
PubMed: 37591902
DOI: 10.1038/s41598-023-40072-1 -
Frontiers in Plant Science 2023Plant-microbe interactions are a phenomenal display of symbiotic/parasitic relationships between living organisms. Plant growth-promoting rhizobacteria (PGPR) are some...
Plant-microbe interactions are a phenomenal display of symbiotic/parasitic relationships between living organisms. Plant growth-promoting rhizobacteria (PGPR) are some of the most widely investigated plant-beneficial microbes due to their capabilities in stimulating plant growth and development and conferring protection to plants against biotic and abiotic stresses. As such, PGPR-mediated plant priming/induced systemic resistance (ISR) has become a hot topic among researchers, particularly with prospects of applications in sustainable agriculture. The current study applies untargeted ultra-high performance liquid chromatography-high-definition mass spectrometry (UHPLC-HDMS) to investigate PGPR-based metabolic reconfigurations in the metabolome of primed wheat plants against f. sp. (). A seed bio-priming approach was adopted, where seeds were coated with two PGPR strains namely and (T22) and grown under controlled conditions in a glasshouse. The plants were infected with one-week post-germination, followed by weekly harvesting of leaf material. Subsequent metabolite extraction was carried out for analysis on a UHPLC-HDMS system for data acquisition. The data was chemometrically processed to reveal the underlying trends and data structures as well as potential signatory biomarkers for priming against . Results showed notable metabolic reprogramming in primary and secondary metabolism, where the amino acid and organic acid content of primed-control, primed-challenged and non-primed-challenged plants were differentially reprogrammed. Similar trends were observed from the secondary metabolism, in which primed plants (particularly primed-challenged) showed an up-regulation of phenolic compounds (flavonoids, hydroxycinnamic acids-HCAs- and HCA amides) compared to the non-primed plants. The metabolomics-based semi-quantitative and qualitative assessment of the plant metabolomes revealed a time-dependent metabolic reprogramming in primed-challenged and primed-unchallenged plants, indicating the metabolic adaptations of the plants to stripe rust infection over time.
PubMed: 37123830
DOI: 10.3389/fpls.2023.1103413 -
Functional Plant Biology : FPB Jun 2023Bacteria that enhance plant growth and development and are found in the vicinity of roots are referred to as plant growth-promoting rhizobacteria. Some beneficial...
Bacteria that enhance plant growth and development and are found in the vicinity of roots are referred to as plant growth-promoting rhizobacteria. Some beneficial bacteria help plant tolerance to many hazardous chemical elements. In this context, Cupriavidus basilensis , Novosphingobium humi , Bacillus zanthoxyli , Bacillus sp., Paenibacillus alvei , Ancylobacter aquaticus and Ralstonia syzygii metal-tolerant rhizospheric bacteria were isolated from rhizospheric soil associated with Bacopa monnieri . The beneficial effects of rhizospheric bacteria on B. monnieri plant physiology and biochemical responses were investigated under pot conditions at two levels (100μM and 500μM) of CuSO4 or FeCl3 . N. humi , A. aquaticus and R. syzygii bacterial strains were associated with significantly increased height and biomass under normal and stress conditions. An assay for indole acetic acid in isolated rhizospheric bacteria found differential secretion except Bacillus zanthoxyli . Bacoside A is a major phytocompound in B. monnieri with medicinal value; maximum induction was observed in the R. syzygii treatment. High concentration of copper and iron salts negatively influenced height, biomass and photosynthetic pigments; however N. humi , A. aquaticus , Bacilllus sp. and R. syzygii beneficial bacterial helped plants under stress conditions. Moreover, a significant enhancement in chlorophyll a and b was noticed in C. basilensis , B. zanthoxyli , Bacilllus sp., P. alvei and R. syzygii treatments, without much influence on carotenoid levels. Therefore, the present study emphasises the importance of isolating plant growth-promoting rhizobacteria for use in bacopa plants exposed to metals such as copper and iron in soil.
Topics: Copper; Iron; Bacopa; Chlorophyll A; Bacteria; Gallionellaceae; Soil
PubMed: 37045602
DOI: 10.1071/FP22263